Pumps - Classification According to the types of impellers

Classification According to THE TYPES OF IMPELLERS

On the basis of the liquid inlet design, impellers are classified as Single Suction Type and Double Suction Type.

1. SINGLE SUCTION IMPELLER

 In a Single Suction Impeller, the liquid enters the suction eye on one side only. Single suction impellers are used for small units, because of ease of manufacture. The initial cost is low. Pump maintenance is also easier. It is used for pumps handling suspended matter, like sewage. In multi stage pumps, single suction impellers are almost universally used.

2. DOUBLE SUCTION IMPELLER

 In the Double Suction Impeller, two single suction impellers are cast back-to-back. Therefore, the liquid enters the impeller simultaneously from both the sides. Double suction impeller is favoured in single stage pumps. Also, the greater suction area permits the pump to operate with less suction head for a given capacity than with a single suction impeller.